Which of these was the dominant plant group at the time that dinosaurs were the dominant animals?

a. bryophytes

b. charophyceans

c. angiosperms

d. gymnosperms

e. seedless vascular plants

Answer: c. angiosperms

Explanation: Most of the dinosaurs that existed in the late Cretaceous period, when flowering plants supplied plant-eating dinosaurs like the hadrosaurs with nutritious food. Angiosperms such magnolias, palms, laurel, early sycamores and barberry existed and supplied the dinosaurs the nutrients they required to survive.

Angiosperms

Explanation:

angiosperms or flowering plants developed during the Early Cretaceous about the same time dinosaurs were the dominant animals. They were really fast-growing and adaptable that many dinosaurs fed on them during the end of Cretaceous, also they could deliver nutrient-rich tissues at a faster rate than other plants.